Histamine release from leucocytes during migraine attack.

Spontaneous histamine release (SHR) from leucocytes (basophils) of 27 migraine patients was investigated during various phases of attack. Mean SHR during the first 3 h of attack (33.7%) was increased compared with the mean SHR from leucocytes of healthy persons (15.9%), but differed insignificantly from the mean SHR in symptom-free periods. Histamine release (HR) from leucocytes of healthy persons suspended in migraine sera from different time-periods of attack was also increased compared with HR in control sera, i.e. high HR could be induced by passive transfer of serum. But the mean HRs in sera from different time-periods of attack were insignificantly different from the mean HR in sera from symptom-free periods. The increased SHR may contribute to vascular hyperreactivity in migraine.